The Linux Mint team announced that they built a new utility to upgrade the Linux Mint significant versions. It’s called the “mintupgrade2”. It is currently under development and planned for upgrading to the major versions—for example, Linux Mint 20 to 21 and not the minor version upgrades.
Although you can upgrade the versions using the standard apt commands, however, the Mint team believes major version upgrades are tricky. It would be difficult for the new users to perform a seamless upgrade because it involves the terminal and a set of complex steps with commands.
Moreover, the GUI is a wrapper with additional features to the mintupgrade program, which brings a set of pre-system checks and upgrade processes with a one-click Fix.
See Linux Mint Upgrade Tool - Here's How it Works
A detailed look at the Linux Mint Upgrade tool (mintupgrade) with a hands-on on how it works with details about it performance.